Billionaire Steve Schwarzman is bringing Waldorf-Astoria to the world.

His Blackstone Group, which bought the mid-priced Hilton Hotels chain for $27 billion, is in the early stages of an aggressive worldwide expansion of the upscale Waldorf-Astoria brand in an attempt to boost profits and save what until recently looked like one of the firm’s worst investments.

Already, Waldorf, which had just four locations when he bought it in 2007, including the storied 100-year-old Park Avenue flagship, has expanded to include 23 hotels from Orlando, Fla., to Shanghai.

Schwarzman has plans to expand that number to 80 over the next several years — with construction under way in Jerusalem, Panama City and London’s Syon Park.

The Waldorf-Astoria expansion, so far, revolves around licensing out one of the most famous brands in the hotel industry to international developers. That way Blackstone’s Hilton doesn’t have to lay out the cash as builder.

Hilton will manage these sites and collect a 1.5-percent to 2-percent fee for running the hotels and then perhaps 7 percent of gross profit, an additional source said.

Hilton is seeing an explosive demand from developers in international cities that do not have many luxury hotels, the source said.

“If you are a developer in one of these places you can make 30 to 40 percent more revenue [for a luxury hotel] by adding the Waldorf name,” the source added.

Blackstone also is putting the expansion pedal to the metal when it comes to the equally upscale Conrad brand — named after Hilton founder Conrad Hilton.

The firm plans to double the 14 hotels that now carry the name over the next 2½ years, including a Battery Park location this year.

The goal is to expand the Conrad brand to be equal in size to Waldorf, The Post has learned. The Waldorf is more classic and Conrad is contemporary luxury, according to Hilton’s marketing.

“This is now only in the early stages,” a person close to the situation said.

For Blackstone there is little to lose: Hilton carries a sizable debt load from the 2007 leveraged buyout and creating additional revenue streams will help it deal with its $16 billion of debt.

Blackstone put down only $5.7 billion in buying Hilton and borrowed the rest of the purchase price.

In April it completed a debt restructuring that cut Hilton’s debt to $16 billion and extended principal payments until 2015.

If it had not succeeded in the restructuring, Hilton reportedly would have had to sell assets to make interest payments.

Blackstone said its investment is now worth more than what it put down, and is expecting to make big profits from Hilton, sources said.